[GHC] #14379: Regression - GHC 2.8.1 Consumes All Memory On Build

[GHC]

#14379: Regression - GHC 2.8.1 Consumes All Memory On Build
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        Reporter:  jm4games          |                Owner:  (none)
            Type:  bug               |               Status:  new
        Priority:  high              |            Milestone:
       Component:  Compiler          |              Version:  8.2.1
      Resolution:                    |             Keywords:
Operating System:  Linux             |         Architecture:  x86_64
 Type of failure:  Compile-time      |  (amd64)
  crash or panic                     |            Test Case:
      Blocked By:                    |             Blocking:
 Related Tickets:                    |  Differential Rev(s):  8.0.2
       Wiki Page:                    |
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Comment (by simonpj):

 This would be worth merging to 8.2.

 I have not added a test because the repro case is tricky.

 My change deliberately reduces the amount of specialisation that
 `SpecConstr` does; but I suppose it's possible that some other important
 use-case will get worse.  But I think it's unlikely.   Worth a check on
 `perf.haskell.org`.

-- 
Ticket URL: <http://ghc.haskell.org/trac/ghc/ticket/14379#comment:6>
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